This is not needed generally, and might prevent catching bugs where
labels are not bound correctly. Instead, only unuse labels on errors.

R=mstarzinger@chromium.org

Change-Id: I1dc77ea21ca80c5be801f17ba284908e1c04abe0
Reviewed-on: https://chromium-review.googlesource.com/c/1443051
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59173}